基于XSBase270平台的AVS解码器亚像素插值优化  

INTERPOLATION OPTIMIZATION OF SUB-PIXEL IN AVS DECODER BASED ON XSBASE270 PLATFORM

作　　者：谢黎[1] 张睿[1] 

机构地区：[1]复旦大学软件学院,上海201203

出　　处：《计算机应用与软件》2010年第7期219-222,267,共5页Computer Applications and Software

摘　　要：亚像素样本插值是视频解码器中计算量最大、耗时最长的部分,在我国第二代信源编码标准AVS的解码器中也不例外。通过图像扩展避免了获取整像素样本时的边界判断;根据运动矢量判断是否需要进行水平、垂直方向的色度分像素插值,据此对色度插值分四种情况分别实现;并且以查表方式实现了亮、色度插值时的分支跳转,减少跳转耗时。结合上述三种方法,提高了XS-Base270平台上AVS解码器的亚像素插值部分的性能,在完全不影响解码质量的情况下,减少了20%到30%亚像素插值耗费的时间。Sub-pixel interpolation is always the most time-consuming part in video decoders and needs lots of calculation,which does not make any exception in decoder of AVS,which is the second generation of source coding standard of our country.In this paper,picture padding is used to avoid edge clips when getting the integer pixels sample.Implementation of chroma sub-pixel interpolation in vertical or horizontal direction is determined by motion vector,according to it the chroma interpolation is to be executed in four circumstances respectively.Also branch jump in brightness and chroma interpolation is implemented with table looking up,which reduces the consuming time.With the three methods mentioned above,the sub-pixel interpolation part of AVS software decoder on XSBase270 platform is optimized by 20% to 30% in time consuming without any loss of quality.

关 键 词：AVS 运动补偿 亚像素插值 优化 XSBase270 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]